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Published on: March 12, 2015
Typhi genes expressed during infection or involved in pathogenesis
1Department of Microbiology and Immunology, University of Montreal, C.P. 6128 Succursale Centre-Ville, Montréal, Québec, Canada, H3C 3J7. france.daigle@umontreal.ca
Journal of Infection in Developing Countries
|September 12, 2009
Summary
Salmonella Typhi causes typhoid fever but lacks animal models. Researchers studied its behavior in human macrophages, identifying key genes for understanding this human-specific pathogen.
Area of Science:
- Microbiology
- Infectious Diseases
- Pathogenesis
Background:
- Salmonella enterica serovar Typhi (Typhi) is a human-restricted pathogen causing typhoid fever.
- Lack of suitable animal models hinders understanding of host-pathogen interactions.
- Macrophages are a valuable alternative model for studying Salmonella pathogenesis.
Purpose of the Study:
- To identify genes expressed by Typhi within human macrophages.
- To investigate Typhi genes involved in host cell interactions.
- To understand the intracellular lifestyle of this human-specific pathogen.
Main Methods:
- Review of studies analyzing gene expression of Typhi during macrophage infection.
- Analysis of identified Typhi immunogenic proteins in typhoid patients.
- Examination of known and unknown virulence factors expressed during infection.
Main Results:
- Typhi genes expressed within human macrophages have been identified.
- Known Salmonella virulence factors, including SPI-2 genes, are expressed.
- Numerous Typhi genes with unknown functions are also expressed during macrophage infection.
Conclusions:
- Human macrophages serve as a valid model for studying Typhi pathogenesis.
- Further investigation of unknown-function genes is crucial for understanding intracellular survival.
- Elucidating these genes is key to developing strategies against typhoid fever.
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